The present invention relates to a structure for supporting a transducer for recording or reproducing information on or from a recording medium mainly by an interaction with the recording medium, specifically, by the action of light, heat, magnetic field, or the like.
As a conventional example of a transducer-supporting structure, for example, a structure for supporting a magnetic core for magnetic recording is cited. As a medium, a magnetic tape or a flexible disk has been used, and in recent years, a minidisk (hereinafter abbreviated to MD) has been widely used as a magneto-optical recording medium mainly for music. The MD is based on the use of a sliding-type magnetic head slider for magneto-optical field modulation overwrite.
Next, a magnetic head structure mainly for MD will be discussed as an example of a conventional transducer-supporting structure. This example has been disclosed in Japanese Patent Laid-Open No. 6-195851. FIG. 10(a) shows an entire structure.
In FIG. 10(a), reference numeral 101 denotes a slider serving as a transducer mounting section. In general, the main function of the transducer mounting section is to interface with a medium. In this example, the slider comes into slidable contact with the medium to maintain a distance between a transducer and the medium.
The slider for a fixed magnetic disk keeps the distance between the transducer and the medium by means of floating. For the magnetic tape, flexible disk, and the like, although the transducer itself comes into contact with the medium, the contact pressure between the medium and the transducer is decreased by the expansion of sliding face, by which the transducer is prevented from wearing.
The slider 101 is mounted with a magnetic core 102 having an E shape in cross section, formed of ferrite etc., and a coil 104 (described later), both of which serve as a transducer. Reference numeral 103 denotes a suspension formed of a metallic elastic material such as stainless steel, beryllium copper, and phosphor bronze. The slider 101 is connected to the distal end of the suspension 103.
The details of the sliding face of the slider 101, which have been disclosed in Japanese Patent Laid-Open No. 7-129902, are shown in FIG. 10(b). On the face opposed to disk of the slider 101, a cylindrical face 101a that comes into contact with a disk 10 (described later) is formed as a sliding face. Reference numeral 102a denotes a magnetic pole exposed on the disk side of the magnetic core 102. The cylindrical face 101a projects by a predetermined amount toward the disk from the magnetic pole 102a. 
The slider 101 including the cylindrical face 101a uses a slidable resin material having high wear resistance and some degree of lubricity on the face opposed to disk, which has an effect of preventing the slider 101 and the disk 10 from wearing.
FIG. 11 shows an essential part of the distal end of a magnetic head structure. A tongue 103c is formed at the distal end of the suspension 103, and is connected to the slider 101.
When the slider 101 comes into slidable contact with the disk 10, which is a recording medium, a spring portion 103a is deformed elastically to apply a predetermined load in the direction toward the disk to the slider 101. Thereby, a gimbal portion 103b is deformed elastically to keep the relative posture of the slider 101 and the disk 10 with respect to the disk inclination, so that the magnetic pole 102a is brought close to a recording film of the disk 10.
FIG. 12 shows a sliding state. The slider 101 serving as a transducer mounting section has a box portion. In the box portion, the aforementioned magnetic core 102 is housed and fixed, and also an inside bottom face S of the box portion, which is in contact with the lower end face of the magnetic core 102, plays a role in determining the relative height of the magnetic core 102. The disk 10 moves in the direction indicated by an arrow A.
In this state, a modulated magnetic field produced by the coil 104 is induced by the magnetic core 102 and is applied from the magnetic pole 102a to the recording film heated by a converged laser beam, by which thermomagnetic recording is performed.
However, the above-described conventional transducer-supporting structure has problems described below.
In order to enhance the performance of equipment, for example, in order to increase the transfer rate of recorded information, it is necessary to increase the modulation frequency of magnetic field. Also, in order to achieve a high density, it is necessary to increase the intensity of magnetic field. Power consumption in the magnetic core 102 and the coil 104, serving as an electromagnetic transducer, is caused by an eddy current loss and a high frequency loss such as a skin effect in the former case and coil resistance etc. in the latter case.
The consumed electric power turns to heat, which raises the temperatures of both of the magnetic core 102 and the coil 104. Since the slider 101 is made of a resin material, which is a kind of thermal insulator, it is difficult to dissipate the heat of the electromagnetic transducer within the slider 101, so that slight generation of heat leads to a great increase in temperature.
On the other hand, a magnetic material used for the magnetic core etc. generally has a Curie point. When a high-frequency large current is caused to flow, a temperature rise exceeding the Curie point due to the generation of heat loses the magnetism and extremely decreases the impedance. Therefore, there occurs a thermorunaway phenomenon that a large current flows, resulting in a temperature rise, and finally the burning of coil and the destruction of driving circuit take place.
Also, for another transducer, for example, an electro-optical transducer such as laser, a shorter wavelength is important to high-density recording and reproduction. However, light with a short wavelength has high energy, so that heat is generated greatly. On the other hand, for a semiconductor laser, the operating temperature has a great influence on the service life, so that a shorter wavelength cannot be achieved easily.
That is, in various types of transducers, a temperature rise greatly restricts the enhancement of performance.
Also, in the conventional example, the magnetic core 102 is fixed to the slider 101 by means of bonding etc. However, a change in temperature occurs as described above, and the coefficient of thermal expansion differs greatly between the magnetic core 102 and the slider 101. Also, the slider 101 has a poor adhesive property because of being made of a slidable resin. Therefore, if thermal expansion and contraction are repeated for a long period of time, there arises a problem of reliability in that adhesion is lost, and thus the magnetic core 102 floats from the slider 101, so that a sufficient magnetic field cannot be given to the recording film.
The present invention has been achieved to solve the above problems, and accordingly an object thereof is to provide a highly reliable transducer-supporting structure in which a rise in temperature is reduced, whereby the performance can be enhanced easily.
One aspect of the present invention is a transducer-supporting structure, characterized in that said structure at least comprises:
a transducer for recording and reproducing information on and from a medium;
a transducer mounting section which is mounted with said transducer and comes into contact with said medium by means of mechanical action or keeps a fixed distance from said medium;
a suspension which supports said transducer mounting section and elastically positions said transducer in the direction such as to bring and separate said transducer close to and from said medium; and
a thermal coupling member formed of a part of said suspension for thermally coupling said transducer with said suspension in direct contact with said transducer, and
at least a part of heat generated in said transducer is dissipated through said suspension.
Another aspect of the present is the transducer-supporting structure, characterized in that said thermal coupling member has an elastic restoring force, and is in contact with said transducer.
Still another aspect of the present invention is the transducer-supporting structure, characterized in that said transducer is an electromagnetic transducer.
Yet still another aspect of the present invention is the transducer-supporting, characterized in that said transducer is an electro-optical transducer.
Still yet another aspect of the present invention is a transducer-supporting structure, characterized in that said structure at least comprises:
a transducer for recording and reproducing information on and from a medium;
a transducer mounting section which is mounted with said transducer and comes into contact with said medium by means of mechanical action or keeps a fixed distance from said medium;
a suspension which supports said transducer mounting section and elastically positions said transducer in the direction such as to bring and separate said transducer close to and from said medium; and
a thermal coupling member for thermally coupling said transducer with said suspension, and
said thermal coupling member and said transducer or said thermal coupling member and said suspension are at least partially coupled thermally with each other via a viscous fluid; and
at least a part of heat generated in said transducer is dissipated through said suspension.
A further aspect of the present is a transducer-supporting structure, characterized in that said structure at least comprises:
a transducer for recording and reproducing information on and from a medium;
a transducer mounting section which is mounted with said transducer and comes into contact with said medium by means of mechanical action or keeps a fixed distance from said medium;
a suspension which supports said transducer mounting section and elastically positions said transducer in the direction such as to bring and separate said transducer close to and from said medium; and
a thermal coupling member for thermally coupling said transducer with said suspension, and
said thermal coupling member is a gel-form substance, and said transducer and said suspension are coupled thermally with each other via said gel-form substance; and
at least a part of heat generated in said transducer is dissipated through said suspension.
A still further aspect of the present invention is a transducer-supporting structure, characterized by at least comprising:
a transducer for recording and reproducing information on and from a medium;
heat dissipating means is formed integrally with said transducer; and
a suspension for holding said transducer at a desired position with respect to said recording medium.
A yet further aspect of the present invention is the transducer-supporting, characterized in that said transducer is an electromagnetic transducer.
FIG. 7 shows an essential part of a transudcer-supporting structure in accordance with a third embodiment of the present invention. A slider 1, a magnetic core 2, a coil 4, and a disk 10 are the same as those elements of the first embodiment. Although the whole of a suspension is not shown in FIG. 7, the suspension is approximately the same as the suspension 3 of the first embodiment, and a gimbal portion 23b is the same as the gimbal portion 3b of the first embodiment.